[Towertalk] LPA designs

[Jon Ogden]

on 11/15/02 1:41 PM, S. J. Blackwell at w5lu@hotmail.com wrote:

> I have had a 5El 20M log-yagi up for 15+ years. Bandwith, front to back and
> front to side are the best I have ever had. There are 3 driven elements, and
> standard ref and dir. I always do well in pile ups. Previous antennas over
> 50yrs of ham radio have been 2 el yagi, CL33, TA33, TH6, 204BA and 205BA as
> well as many other homemade types. None have compared to the log-yagi. I
> realize this is totally subjective, but it will take a lot more than
> computer modelling ( which I have done) to get me to change.
> 73

Log-Yagi's are great designs.  You have more active elements and more
parasitic elements to give you increased gain as well.  The log-yagi though
is still a relatively narrowband design compared to a standard LPDA.  I have
an old KLM 432 beam this way and it has incredible bandwidth.  Yagis are
inherently very narrow band.  Doesn't matter much in the relatively small
frequency ranges of HF, yet I do believe you would get better performance
from a log type driven element as you'd certainly have much better BW across
say, the entire 20 meter band.

73,

Jon
NA9D

-------------------------------------
Jon Ogden
NA9D (ex: KE9NA)

Citizen of the People's Democratic Republik of Illinois

Life Member: ARRL, NRA
Member:  AMSAT, DXCC

http://www.qsl.net/na9d

"A life lived in fear is a life half lived."